Tantrum

Tantrum was a Lockheed Martin technology demonstrator carrying a wideband electronically steerable antenna (ESA) on a Terran Orbital Nebula satellite bus, designed to validate rapid on-orbit capabilities for U.S. military operators. The flight, designated "Fly the Lightning", was Firefly's second dedicated responsive-space military mission, following Victus Nox (TacRS-3) in September 2023.

A software bug in the second stage's guidance, navigation, and control (GNC) algorithm prevented the stage from correctly orienting before the planned circularization burn - the engine failed to relight, leaving Tantrum in a lower elliptical orbit than intended. Despite the missed orbit, Lockheed Martin reported that the satellite completed its primary mission objectives.